FAQ: Is there a difference in cutting close to the ends between ScaI-HF and ScaI?

No. When tested on a series of five oligos (19-23 bases in length) containing the restriction site and an additional 1 to 5 A/T bases from the end, both enzymes cut the oligo with 1 base pair from the end. When designing primers, NEB recommends adding 6 extra bases to ensure against experimental failure due to variation in substrate and reaction conditions.